Acoustic signal processing apparatus, acoustic signal processing method and program

Abstract

Crosstalk correction processing is performed on a first binaural signal based on a sound source opposite side HRTF and a second binaural signal based on a sound source side HRTF. A first acoustic signal and a second acoustic signal are generated. A component of a first frequency band, in which a first notch of the sound source opposite side HRTF appears, and a component of a second frequency band, in which a second notch appears, are attenuated in an input signal or the second binaural signal, thereby attenuating the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal. An auxiliary signal including a component of a third frequency band of the input signal or the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, is added to the first acoustic signal, and a third acoustic signal is generated. The present technology can be applied to, for example, an AV amplifier.

The invention claimed is: 
     
       1. An acoustic signal processing apparatus comprising:
 a first transaural processing unit that generates a first binaural signal for a first input signal, which is an acoustic signal for a first virtual sound source deviated to left or right from a median plane of a predetermined listening position, by using a first head-related transfer function between an ear of a listener at the listening position farther from the first virtual sound source and the first virtual sound source, generates a second binaural signal for the first input signal by using a second head-related transfer function between an ear of the listener closer to the first virtual sound source and the first virtual sound source, and generates a first acoustic signal and a second acoustic signal by performing crosstalk correction processing on the first binaural signal and the second binaural signal as well as attenuates a component of a first frequency band and a component of a second frequency band in the first input signal or the second binaural signal to attenuate the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal, the first frequency band being lowest and the second frequency band being second lowest at a predetermined first frequency or more of frequency bands in which notches, which are negative peaks with amplitude of a predetermined depth or deeper, appear in the first head-related transfer function; and 
 a first auxiliary signal synthesizing unit that generates a third acoustic signal by adding a first auxiliary signal to the first acoustic signal, the first auxiliary signal including a component of a predetermined third frequency band of the first input signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, or the component of the third frequency band of the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated. 
 
     
     
       2. The acoustic signal processing apparatus according to  claim 1 , wherein the first transaural processing unit comprises:
 an attenuating unit that generates an attenuation signal obtained by attenuating the component of the first frequency band and the component of the second frequency band of the first input signal; and 
 a signal processing unit that integrally performs processing for generating the first binaural signal obtained by superimposing the first head-related transfer function on the attenuation signal and the second binaural signal obtained by superimposing the second head-related transfer function on the attenuation signal and the crosstalk correction processing on the first binaural signal and the second binaural signal, and 
 the first auxiliary signal includes the component of the third frequency band of the attenuation signal. 
 
     
     
       3. The acoustic signal processing apparatus according to  claim 1 , wherein the first transaural processing unit comprises:
 a first binauralization processing unit that generates the first binaural signal obtained by superimposing the first head-related transfer function on the first input signal; 
 a second binauralization processing unit that generates the second binaural signal obtained by superimposing the second head-related transfer function on the first input signal as well as attenuates the component of the first frequency band and the component of the second frequency band of the first input signal before the second head-related transfer function is superimposed or of the second binaural signal after the second head-related transfer function is superimposed; and 
 a crosstalk correction processing unit that performs the crosstalk correction processing on the first binaural signal and the second binaural signal. 
 
     
     
       4. The acoustic signal processing apparatus according to  claim 3 , wherein the first binauralization processing unit attenuates the component of the first frequency band and the component of the second frequency band of the first input signal before the first head-related transfer function is superimposed or of the first binaural signal after the first head-related transfer function is superimposed. 
     
     
       5. The acoustic signal processing apparatus according to  claim 1 , wherein the third frequency band includes at least a lowest frequency band and a second lowest frequency band at a predetermined second frequency or more of frequency bands in which the notches appear in a third head-related transfer function between one speaker of two speakers arranged left and right with respect to the listening position and one ear of the listener, a lowest frequency band and a second lowest frequency band at a predetermined third frequency or more of frequency bands in which the notches appear in a fourth head-related transfer function between an other speaker of the two speakers and an other ear of the listener, a lowest frequency band and a second lowest frequency band at a predetermined fourth frequency or more of frequency bands in which the notches appear in a fifth head-related transfer function between the one speaker and the other ear, or a lowest frequency band and a second lowest frequency band at a predetermined fifth frequency or more of frequency bands in which the notches appear in a sixth head-related transfer function between the other speaker and the one ear. 
     
     
       6. The acoustic signal processing apparatus according to  claim 1 , further comprising:
 a first delaying unit that delays the first acoustic signal by a predetermined time before the first auxiliary signal is added; and 
 a second delaying unit that delays the second acoustic signal by the predetermined time. 
 
     
     
       7. The acoustic signal processing apparatus according to  claim 1 , wherein the first auxiliary signal synthesizing unit adjusts a level of the first auxiliary signal before the first auxiliary signal is added to the first acoustic signal. 
     
     
       8. The acoustic signal processing apparatus according to  claim 1 , further comprising:
 a second transaural processing unit that generates a third binaural signal for a second input signal, which is an acoustic signal for a second virtual sound source deviated to left or right from the median plane, by using a seventh head-related transfer function between an ear of the listener farther from the second virtual sound source and the second virtual sound source, generates a fourth binaural signal for the second input signal by using an eighth head-related transfer function between an ear of the listener closer to the second virtual sound source and the second virtual sound source, and generates a fourth acoustic signal and a fifth acoustic signal by performing the crosstalk correction processing on the third binaural signal and the fourth binaural signal as well as attenuates a component of a fourth frequency band and a component of a fifth frequency band in the second input signal or the fourth binaural signal to attenuate the component of the fourth frequency band and the component of the fifth frequency band of the fifth acoustic signal, the fourth frequency band being lowest and the fifth frequency band being second lowest at a predetermined sixth frequency or more of frequency bands, in which the notches appear in the seventh head-related transfer function; 
 a second auxiliary signal synthesizing unit that generates a sixth acoustic signal by adding a second auxiliary signal to the fourth acoustic signal, the second auxiliary signal including the component of the third frequency band of the second input signal, in which the component of the fourth frequency band and the component of the fifth frequency band are attenuated, or the component of the third frequency band of the fourth binaural signal, in which the component of the fourth frequency band and the component of the fifth frequency band are attenuated; and 
 an adding unit that adds the third acoustic signal and the fifth acoustic signal and adds the second acoustic signal and the sixth acoustic signal in a case where the first virtual sound source and the second virtual sound source are separated to left and right with reference to the median plane, and adds the third acoustic signal and the sixth acoustic signal and adds the second acoustic signal and the fifth acoustic signal in a case where the first virtual sound source and the second virtual sound source are on a same side with reference to the median plane. 
 
     
     
       9. The acoustic signal processing apparatus according to  claim 1 , wherein the first frequency is a frequency at which a positive peak appears in a vicinity of 4 kHz of the first head-related transfer function. 
     
     
       10. The acoustic signal processing apparatus according to  claim 1 , wherein the crosstalk correction processing is processing that cancels, for the first binaural signal and the second binaural signal, an acoustic transfer characteristic between a speaker of two speakers arranged left and right with respect to the listening position on an opposite side of the first virtual sound source with reference to the median plane and the ear of the listener farther from the first virtual sound source, an acoustic transfer characteristic between a speaker of the two speakers on a side of the virtual sound source with reference to the median plane and the ear of the listener closer to the first virtual sound source, crosstalk from the speaker on the opposite side of the first virtual sound source to the ear of the listener closer to the first virtual sound source, and crosstalk from the speaker on the side of the virtual sound source to the ear of the listener farther from the first virtual sound source. 
     
     
       11. An acoustic signal processing method comprising:
 a transaural processing step that generates a first binaural signal for an input signal, which is an acoustic signal for a virtual sound source deviated to left or right from a median plane of a predetermined listening position, by using a first head-related transfer function between an ear of a listener at the listening position farther from the virtual sound source and the virtual sound source, generates a second binaural signal for the input signal by using a second head-related transfer function between an ear of the listener closer to the virtual sound source and the virtual sound source, and generates a first acoustic signal and a second acoustic signal by performing crosstalk correction processing on the first binaural signal and the second binaural signal as well as attenuates a component of a first frequency band and a component of a second frequency band in the input signal or the second binaural signal to attenuate the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal, the first frequency band being lowest and the second frequency band being second lowest at a predetermined frequency or more of frequency bands in which notches, which are negative peaks with amplitude of a predetermined depth or deeper, appear in the first head-related transfer function; and 
 an auxiliary signal synthesizing step that generates a third acoustic signal by adding an auxiliary signal to the first acoustic signal, the auxiliary signal including a component of a predetermined third frequency band of the input signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, or the component of the third frequency band of the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated. 
 
     
     
       12. A program for causing a computer to execute processing including:
 a transaural processing step that generates a first binaural signal for an input signal, which is an acoustic signal for a virtual sound source deviated to left or right from a median plane of a predetermined listening position, by using a first head-related transfer function between an ear of a listener at the listening position farther from the virtual sound source and the virtual sound source, generates a second binaural signal for the input signal by using a second head-related transfer function between an ear of the listener closer to the virtual sound source and the virtual sound source, and generates a first acoustic signal and a second acoustic signal by performing crosstalk correction processing on the first binaural signal and the second binaural signal as well as attenuates a component of a first frequency band and a component of a second frequency band in the input signal or the second binaural signal to attenuate the component of the first frequency band and the component of the second frequency band of the first acoustic signal and the second acoustic signal, the first frequency band being lowest and the second frequency band being second lowest at a predetermined frequency or more of frequency bands in which notches, which are negative peaks with amplitude of a predetermined depth or deeper, appear in the first head-related transfer function; and 
 an auxiliary signal synthesizing step that generates a third acoustic signal by adding an auxiliary signal to the first acoustic signal, the auxiliary signal including a component of a predetermined third frequency band of the input signal, in which the component of the first frequency band and the component of the second frequency band are attenuated, or the component of the third frequency band of the second binaural signal, in which the component of the first frequency band and the component of the second frequency band are attenuated.